Systems and methods for accessing a furnace melt

ABSTRACT

A method and apparatus for accessing a furnace melt are provided. Preferably, the method and apparatus provide for the safe and efficient access to the melt. According to one aspect of the invention used in a steel-making process in an electric arc furnace, a furnace aperture burner/lance provides a flame for heating the melt, a lance device for injecting oxygen into the furnace, or both. To access the melt, the furnace aperture burner/lance is disengaged, access is provided to the melt through the furnace aperture, and the furnace aperture burner/lance is reengaged when the access is concluded.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 11/500,258, now U.S. Pat. No. 7,704,445, filed Aug. 7, 2006,and entitled “Systems and Methods for Accessing a Furnace Melt,” whichis a continuation-in-part of U.S. patent application Ser. No.11/170,254, now U.S. Pat. No. 7,704,444, filed Jun. 29, 2005, andentitled “Method and Apparatus for Testing Characteristics of a FurnaceMelt.” Both of these applications are incorporated by reference as ifset out fully below.

TECHNICAL FIELD

The present invention relates generally to a method and apparatus usedin metal melting, refining, and processing, and more particularly, amethod and apparatus for accessing a furnace melt.

BACKGROUND

Electric arc furnaces (EAFs) make steel by using an electric arc to meltone or more charges of scrap metal, hot metal, iron based materials, orother meltable materials, which is placed within the furnace. ModernEAFs may also make steel by melting DRI (direct reduced iron) alone, orcombined with the hot metal from a blast furnace. In addition to theelectrical energy of the arc, chemical energy is provided by auxiliaryburners using fuel and an oxidizing gas to produce combustion productswith a high heat content to assist the melting.

If the EAF is used as a scrap melter, the scrap burden is charged bydumping it into the furnace through the roof opening from buckets, whichalso may include charged carbon and slag forming materials. A similarcharging method using a ladle for the hot metal from a blast furnace maybe used along with injection of the DRI by a lance to produce theburden. Additionally, these materials could be added through otheropenings in the furnace.

In the melting phase, the electric arc and burners melt the burden intoa molten pool of metal, termed an iron carbon melt, which accumulates atthe bottom or hearth of the furnace. Typically, after a flat bath hasbeen formed by melting of all introduced burden, the electric arcfurnace enters a refining and/or decarburization phase. In this phase,the metal continues to be heated by the arc until the slag formingmaterials combine with impurities in the iron carbon melt and rise tothe surface as slag. During the heating of the iron carbon melt, itreaches the temperature and conditions when carbon in the melt combineswith oxygen present in the bath to form carbon monoxide bubbles.Generally, flows of oxygen are blown into the bath with either lances orburner/lances to produce a decarburization of the bath by the oxidationof the carbon contained in the bath.

The resulting decarburization reduces the carbon content of the bath toa selected level. If an iron carbon melt is under 2% carbon it becomessteel. Except for operations using the hot metal from the Blastfurnaces, the EAF steel making processes typically begin with burdenshaving less than 1% carbon. The carbon in the steel bath is continuallyreduced until it reaches the content desired for producing a specificgrade of steel, down to less than 0.1% for low carbon steels.

The EAF steel making process is an extremely exacting process thatinvolves the simultaneous management of a variety of differentvariables. The numerous variables of the melting process must be keptwithin certain tolerances throughout the process to ensure an accurateand efficient melt is conducted. For instance, chemical energy can beadded at certain stages of the process to facilitate the progression ofthe melt. Additionally, other chemicals can be inserted into the furnaceto alter the state of the melt to progress the steel making process andprotect the furnace equipment. Furthermore, it is desirable to identifywhen the process is complete and the steel is ready for removal. Thesteps involved in the steel making process, including insertingadditional chemical energy, inserting other chemical substances,determining the whether the steel is ready for tapping, and many othernecessary tasks, require that the operator have a safe, effective, andefficient means by which to access the melt. Sometimes, means providedthe operator for accessing the iron carbon melt are inefficient,detrimental to the progression of the steel making process, and provideinsufficient safety precautions for the operator.

First, any opening in an EAF for receiving a lance or takingmeasurements must be kept clear of slag, which can prove particularlydifficult for openings located relatively low in the furnace. This maybe done with a constant flow of air through the opening, if this openingis relatively small. Larger openings require a significant volume ofconstant air flow, which is not preferable since it may be costly toprovide such a high volume of air and because it may cool the furnace.Counteracting such cooling affects is also costly. In practice, theprotection of openings by the flow of compressed air does not result ina clean, unplugged opening.

Second, the furnace operator may be required to inject a variety ofchemicals (fluxes) into the furnace during the steel making process toensure the melt is progressing appropriately. For example, chemicalssuch as, but not limited to, lime, carbon, oxygen, aluminum, andsilicon, may be introduced into the bath to reduce impurities and alterthe chemical composition of the steel. The added chemicals can aid insuch processes as the carburization or decarburization of the melt orthe creation of foamy slag to shield the electric arc and protect thefurnace equipment. The conventional methods of insertion of chemicalsalso require the operator to expose openings in the furnace's roof orupper shell. The lower the position of the openings within a furnace,the more effort required to keep the opening clean. The current trend isto keep the ports, or openings, higher above the level of molten steel.This results in a significant loss of small particles of insertedchemicals through the fume evacuation system of EAFs.

Third, the furnace operator encounters many challenges with theconventional methods of determining whether the melt is ready fortapping. A furnace must reach very high temperatures to melt burden intomolten metal. For example, scrap steel melts at approximately 2768° F.To achieve such high temperatures, steel making furnaces are generallyfully enclosed with a minimal number of openings. Due to the negativepressures in the EAF, furnace openings may allow ambient air into thefurnace and create a cold spots. Additionally, it is typically desirableto raise the temperature of the melt sufficiently above the meltingpoint (typically to 2950° F.-3050° F.) to allow the melt to betransferred from the furnace to a desired location and further processedwithout prematurely solidifying.

Additionally, due to the high temperature and splashing of slag andmolten metal, it is not practical to install a permanent temperaturegauge in the furnace to monitor the temperature of the molten metalbath. Accordingly, steel makers typically use disposable thermocouplesto check the liquid bath temperature. Disposable probes are typicallymounted in cardboard sleeves that slide onto a steel probe pole, whichhas internal electrical contracts. The disposable probe transmits anelectrical signal to the steel pole, which in turn transmits the signalto an electronic unit for interpretation. Additional probes may be usedto determine the carbon content and dissolved oxygen levels in themolten metal. Various disposable temperature and chemical content probesare known in the art.

Typically, disposable probes are inserted into the furnace through theslag door. Unfortunately, there are several drawbacks to measuring thetemperature through the open slag door. For example, when the door isopen, a large amount of cold air can be drawn into the furnace. If themolten metal bath is below the desired temperature, the additional heatlosses due to temperature probing will require more energy to beconsumed to reach the target temperature.

Another draw back to measuring steel bath parameters through the slagdoor involves the process of inserting a probe into the liquid bath.Many years ago, probes were only introduced into the melt manually. Thismanual operation puts the operator at great risk of injury. Today, somesteel plants and foundries still use this manual procedure because mostalternative systems are very costly. Each year, operators are seriouslyinjured or even killed while taking furnace measurements manuallythrough the open slag door. These injuries typically occur whenuncontrollable reactions occur in the furnace thereby causing injury tothe operator.

These reactions are caused by rapid reaction of oxygen and carbon in thefurnace. Oxygen is injected into the steel bath to remove or balanceelements such as, but not limited to, sulfur, phosphorus, manganese,silicon, and carbon. Although carbon reacts quickly with oxygen, as thecarbon concentration in the steel bath decreases below 0.10% by weight,the oxygen-carbon reaction slows down considerably, resulting instratification of molten bath. In order to reduce carbon below 0.05% inthe steel bath, the active or free oxygen level in the steel must beabout 700 ppm. If any material such as slag or scrap were to fall fromthe walls of the furnace into the steel bath, an eruption will occur.The oxidizable elements in the slag or steel will react with the activeoxygen in the steel bath and create, very quickly, a large amount ofcombustible gasses. These gases can erupt with enough force to throwflame, slag, and steel a great distance. In addition, when thecombustible gases created in this reaction are exiting the furnacethrough the slag door, they rapidly combust with the air outside of thefurnace thus increasing the intensity of the reaction.

Such reactions occur so quickly that it creates an explosive effect.Tragically, if such reactions occur while the slag door is open for amanual measurement, the slag boil can overflow the furnace and causegreat harm to the operator. Now, many furnace operators use a large, andexpensive, mobile device for inserting probes into the furnace. Sincethe slag door must remain clear for removing slag from the furnace, adedicated temperature probe insertion tool can not be installed adjacentto the slag door. Rather, the device must either have a very long arm toreach through the slag door to the bath, or it must be mobile so that itcan be moved out of the way of the door for other processes.

When the slag door is opened, any slag and metal trapped at the dooropening must be cleared to allow insertion of the measurement probe.Clearing the door can be done with a large ram that pushes the slag andscrap out of the door opening and into the melt. Since any scrap trappedin the opening is pushed into the melt adjacent to the door, a probeinserted through the door can not easily measure the temperature of themelt. It is a typical practice in the industry to wait for this scrap tobe melted before taking a measurement. This practice adds additionaltime to the melting phase, and therefore additional expense, to thesteel making process.

There are other potential options available for insertion of thetemperature probe, but each has significant drawbacks and is nottypically used in the industry. First, an opening could be provided inthe side wall of the furnace and a temperature probe could be insertedthrough this opening. Unfortunately, there is not a good location forproviding such opening. If the opening were provided low in the furnace,close to the melt, it would become clogged with slag. Thus, the slagwould need to be removed prior to insertion of the probe. Prior to thepresent invention, there was not a device available for easily andefficiently cleaning slag from such an opening. Cleaning the slag fromthe hole is an onerous task because the slag solidifies on the walls ofthe furnace and can become quite thick. Thus, it would be difficult toclean the slag from the opening and insert the temperature probe in anefficient manner.

Alternatively, the opening could be provided very high on the side wallof the furnace where it would be less likely to become clogged withslag. This solution is also not desirable because the access openingwould be far from the melt. Thus, an exceptionally long probe pole wouldbe needed to reach down into the melt. To operate this pole, a long andheavy structure adjacent to the furnace wall must be constructed. Thelocation of this structure is limited by potential interference with themovement of the furnace roof and the scrap bucket during the charge ofmelting material.

Finally, an additional drawback relates to the utilization of differentsystems for the introduction of chemical energy into the EAF shell, suchas burners, oxygen injectors, carbon injectors and others is thestandard practice of modern EAF steel melting. The systems are locatedon different parts of the furnace's shell, or roof, and assist in scrappreheating, melting, steel decarburization and refining through theopening in the shells. These systems only function during certain phasesof the process. During the remainder of the process they must bemaintained in a protective mode to keep the ports clean, such as pilotflame, or for the non-flammable apparatus, compressed air or nitrogenflow. The lower these openings are located in a furnace, the more effortrequired to keep the openings clean. The pilot flame, nitrogen, orcompressed air flow increase the cost of operations and require theconsumption of additional energy to make steel.

Therefore, it would be advantageous to provide a method and apparatusfor accessing the melt through an opening in the furnace.

Therefore, it would be advantageous to provide a method and apparatusfor inserting a lance through an opening in the furnace.

Therefore, it would be advantageous to provide a method and apparatusfor inserting chemicals through an opening in the furnace.

Therefore, it would be advantageous to provide a method and apparatusfor injecting chemicals into a molten metal bath through an opening inthe furnace close to the bath.

Therefore, it would be advantageous to provide a method and apparatusfor measuring the temperature of a molten metal bath through an openingin the furnace, other than the slag door.

Additionally, it would be advantageous to provide a method and apparatusfor injecting chemicals into a molten metal bath through a dedicatedchemical injection aperture.

Additionally, it would be advantageous to provide a method and apparatusfor keeping a dedicated chemical injection aperture clear of slag anddebris without using a constant flow of air.

Additionally, it would be advantageous to provide a furnace with adedicated chemical injection aperture.

Therefore, it would be advantageous to provide a method and apparatusfor protecting the openings in a furnace shell and roofs without usingextensive amount of fuel, oxygen, nitrogen, or compressed air.

SUMMARY

The invention provides a method and apparatus for providing access tothe melt in a metal melt furnace.

According to one aspect of the invention, a furnace aperture plug isreciprocated through a furnace aperture, the furnace aperture plug isretracted from the furnace aperture, access is provided to the furnace,and the furnace aperture plug is inserted into the furnace aperture.

According to another aspect of the invention, a furnace aperture plug isreciprocated through a furnace aperture, the furnace aperture plug isretracted from the furnace aperture, a burner device is enabled toinsert a flame into the furnace through the furnace aperture, and thefurnace aperture plug is inserted into the furnace aperture.

According to another aspect of the invention, a furnace aperture plug isreciprocated through a furnace aperture, the furnace aperture plug isretracted from the furnace aperture, a lance device is inserted throughthe furnace aperture and operated, then the lance device is retractedfrom the aperture, and the furnace aperture plug is inserted into thefurnace aperture.

According to another aspect of the invention, a furnace aperture plug isreciprocated through a furnace aperture, the furnace aperture plug isretracted from the furnace aperture, chemicals are inserted into themelt through the furnace aperture, and the furnace aperture plug isinserted into the furnace aperture.

According to another aspect of the invention, a furnace aperture plug isreciprocated through a furnace aperture, the furnace aperture plug isretracted from the furnace aperture, a furnace probe is inserted throughthe furnace aperture, the furnace probe is retracted from the aperture,and the furnace aperture plug is inserted into the furnace aperture.

According to another aspect of the present invention, a furnace accessapparatus includes a mounting enclosure for protecting the furnaceaccess apparatus and mounting it in the furnace.

According to another aspect of the present invention, the furnaceaperture plug may be reciprocated more than once during a metal meltcycle. Additionally, the furnace aperture plug may be reciprocatedperiodically during the metal melt cycle.

According to another aspect of the present invention, the furnaceaperture plug is reciprocated to remove slag from the furnace aperture.Preferably, the reciprocation of the furnace aperture plug through thefurnace aperture removes at least a portion of slag build up proximatethe furnace aperture. Additionally, when the furnace aperture plug isreciprocated through the furnace aperture, it is extended through theaperture past the wall of the furnace enclosure and then retracted toits original closed position.

According to another aspect of the present invention, a furnace accessapparatus for use in an electric arc furnace comprises a furnaceaperture plug adapted for insertion into a furnace aperture and afurnace aperture plug reciprocator for moving the furnace aperture plug.Preferably, the furnace aperture plug reciprocator is coupled to thefurnace aperture plug and adapted to move the plug between a retractedposition and an inserted position relative to the furnace aperture. Whenthe furnace aperture plug is in an inserted position, it closes thefurnace aperture and prevents slag and other debris from entering thefurnace access apparatus. When the furnace aperture plug is in aretracted position, it allows access to the furnace through the furnaceaperture.

According to another aspect of the present invention, the furnaceaperture plug reciprocator is a telescoping arm adapted to advance andretract the furnace aperture plug.

According to another aspect of the present invention, the furnace accessapparatus mounting enclosure is fluid cooled and adapted to protect thefurnace aperture plug and the furnace probe from the harsh environmentof the furnace.

According to another aspect of the present invention, the furnace accessapparatus is mounted on the refractory step of the furnace and isaccessed through a side wall panel of the furnace.

According to yet another aspect of the present invention, the mountingenclosure includes a deflector for deflecting scrap charged in thefurnace away from the furnace aperture plug. Preferably, the deflectoris a porch sloped toward the inside of the furnace. Additionally, themounting enclosure may include corrugations for retaining slag. The slaghelps insulate the mounting device from the heat of the furnace.

According to another aspect of the present invention, a furnace apertureburner is used in place of or in addition to the furnace aperture plug.A fuel inlet provides a means for delivering fuel to the burner. Thefurnace aperture burner provides heat proximate the furnace apertureand, preferably, prevents slag from building up in the aperture. Thefurnace aperture burner can be disengaged and retracted to allow accessto the melt.

These and other features as well as advantages, which characterize thevarious preferred embodiments of present invention, will be apparentfrom a reading of the following detailed description and a review of theassociated drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectioned side view of an exemplary embodiment of afurnace access apparatus mounted in an electric arc furnace, which isconstructed in accordance with an exemplary embodiment of the presentinvention.

FIG. 2 is a cross-sectioned side view of the furnace access apparatusillustrated in FIG. 1 showing the furnace aperture plug in a retractedposition permitting access through the furnace aperture.

FIG. 3 is a cross-sectioned side view of the furnace access apparatusillustrated in FIG. 1 showing the furnace aperture plug in an insertedposition.

FIG. 4 is a cross-sectioned side view of an exemplary embodiment of afurnace access apparatus mounted in an electric arc furnace, showing afurnace aperture burner/lance in an inserted position, in accordancewith an exemplary embodiment of the present invention.

FIG. 5 is a cross-sectioned side view of the furnace access apparatusillustrated in FIG. 4, showing the furnace aperture burner/lance in aretracted position.

FIG. 6 is a cross-sectioned side view of the furnace access apparatusillustrated in FIG. 1, which shows the furnace aperture plug in both aretracted position and inserted position.

FIG. 7 is a cross-sectioned side view of the furnace access apparatusillustrated in FIG. 1 showing the furnace aperture plug in a retractedposition and a furnace probe inserted through the furnace aperture.

FIG. 8 is a cross-sectioned side view of the furnace access apparatusillustrated in FIG. 1, showing the furnace aperture plug in a retractedposition and a chemical receptacle attached to the furnace receptacle.

FIG. 9 is a cross-sectioned side view of the furnace access apparatusillustrated in FIG. 1, showing the furnace aperture plug in a retractedposition and a chemical receptacle attached to the furnace receptacle.

DETAILED DESCRIPTION

Referring now the drawings, in which like numerals represent likeelements, exemplary embodiments of the present invention are hereindescribed.

FIG. 1 is a cross-sectioned side view of an exemplary embodiment afurnace access apparatus mounted in an electric arc furnace (“EAF”) andwhich is constructed in accordance with an exemplary embodiment of theinvention. In an exemplary embodiment, the furnace 100 melts ferrousscrap, or other iron based materials, by means of an electric arcproduced from one or more electrodes to collect a molten metal bath ormelt 150 in its hearth. The metal bath level varies significantly duringthe melting process. The bath level generally begins with a hot heellevel, which is the iron melt left from the previous heat. As multiplecharges of scrap or other iron base materials are melted, the levelrises. The furnace is typically filled to a level about 12 to 18 inchesdown from the sill line 155. Other steel making processes such as DRImelting and the ConSteel process produce similar bath level changes.Typically, the EAF hearth is generally spherical in shape and is made ofrefractory material able to withstand the high temperature of the moltenmetal. The hearth of the furnace 100 is typically surrounded by an uppershell comprised of a series of fluid cooled panels. It is known that thefluid cooled panels forming the side wall 160 of the furnace 100 can beof several conventional types. These panels are typically supplied withcooling fluid from circumferential supply conduits, which are connectedto cause fluid to circulate through the panels and then exit to carryoff heat.

Alternatively, spray cooled panels may be used in place of fluid cooledpanels. In a typical spray cooled system, two concentric plate shellsseparated by a gap are used. Between the two shells are installednumerous spray nozzles that are adapted to spray the outside of theinner shell (the shell adjacent the interior of the furnace). The fluidsprayed onto the shell cools the shell material. In an alternativeexemplary embodiment, the furnace 100 could be cooled by a device asdisclosed in U.S. patent application Ser. No. 11/361,725, now U.S. Pat.No. 7,483,471, filed Feb. 24, 2006, entitled “Cooling Device For Use inan Electric Arc Furnace.”

The melt 150, generally comprising iron and carbon, is generally coveredwith various amounts of slag, which is produced by the chemicalreactions between the melt and slag forming materials added to thefurnace before or during the melting process of the metal. Once thescrap metal or other burden has been melted, the metal bath 150 isgenerally refined by additives and decarburized by oxygen lancing. Thisproduces the required chemistry for the melt and reduces the carboncontent of the metal to the grade of steel desired.

After the electrodes are turned on, a foamy slag may be developed byinjecting particulate carbon to protect the furnace components fromradiation from the arc. During refining and thereafter, the metal bath150 is typically heated by the electric arc above its meltingtemperature. The superheating is used to allow the metal bath 150 toremain at a high enough temperature while being transported in a ladleand while finishing other process steps. If the melt 150 does notcontain an adequate carbon level for the grade of steel desired then itmust be recarburized by adding carbon to the bath, or to the ladle,during or after tapping of the molten metal. The melt 150 may lack anadequate carbon level because of the materials which were melted to formthe bath or because oxygen lancing has decreased the carbon content tobelow a desired threshold.

FIG. 2 is a cross-sectioned side view of the furnace access apparatusillustrated in FIG. 1. As shown in FIG. 2, a furnace access apparatus200, in accordance with an exemplary embodiment of the presentinvention, generally includes, but is not limited to, a furnace aperture140, a furnace aperture plug 105, a furnace aperture plug reciprocator110, and a furnace receptacle 120. When the furnace aperture plug 105 isin the retracted position, as shown in FIG. 2, the furnace aperture 140provides access to the melt in a position sufficiently proximate themelt to allow for efficient and effective access to the melt for avariety of tasks. In an exemplary embodiment, the furnace receptacle 120is aligned with the furnace aperture 140 for accessing the interior ofthe furnace when the furnace plug is retracted.

Referring back to FIG. 1, the furnace access apparatus 200, ispreferably mounted adjacent an opening in the fluid cooling side wallpanel 160 of the furnace 100. In the illustrated embodiment, themounting enclosure 115 preferably rests on the step 130 formed betweenthe panels of the side wall 160 of the upper shell of the furnace 100and the refractory wall of the hearth 135. Alternatively, the furnaceaccess apparatus 200 could be supported or suspended from anothersuitable structural member of the furnace 100.

The furnace aperture plug 105 and furnace receptacle 120 can be mountedin the furnace access apparatus enclosure 115. The furnace accessapparatus enclosure 115 is preferably mounted low on the side wall 160of the furnace or on the refractory step 130 to provide access close tothe surface of the melt 150. The mounting enclosure 115 also providesprotection for the furnace aperture plug 105 and the furnace receptacle120 from the intense heat of the furnace 100 and mechanical damage fromfalling scrap. In normal operation a slag covering forms on the mountingenclosure 115. The slag covering helps to insulate the mountingenclosure 115 from heat in the furnace.

As shown in FIG. 2, an exemplary embodiment of the furnace accessapparatus enclosure 115 comprises a top fluid cooled panel 240, a frontfluid cooled panel 230, and a bottom fluid cooled panel 250.Additionally, the front fluid cooled panel 230 may comprise an upperportion 234 that is sloped toward the center of the furnace and a lowerportion 235 that is sloped inward toward the side of the furnace.Alternatively, the sloped portion 234 may be part of the top fluidcooled panel 240, or may be used in place of the top fluid cooled panel240. Preferably, the upper portion 234 includes corrugations fortrapping slag, thereby insulating the furnace access apparatus enclosure115 from the intense heat of the furnace. Preferably, the lower portion235 is sloped inward at an angle greater than a wet angle, so that slagwill not accumulate on the surface of the lower portion 235. A wet angleis an angle at which fluid will adhere to the surface although gravitypulls the fluid away from the surface. Typically, the wet angle is up to10 degrees from vertical. The inward slope of the lower portion 235 ofthe front panel 230 of the enclosure 115, allows the furnace aperture140 to be protected from falling scrap by the upper portion 234 of thefront panel 230.

Referring now to FIG. 3, which is a cross-sectioned side view of thefurnace access apparatus enclosure with the furnace aperture plug 105 inits forward position. As shown in FIG. 3, when the furnace aperture plug105 is in its forward (or closed, or inserted) position, the plug 105fills the furnace aperture 140. In this position, the plug 105 preventsslag and other debris from entering the furnace access apparatus 200. Itis typically preferable for the plug 105 to be positioned either flushwith the exterior wall of the enclosure 115, or slightly extendedthrough the aperture 140. If the furnace aperture plug 105 is positionedwithin the aperture such that it is slightly retracted, the furnaceaccess apparatus should still operate correctly. However, it isdesirable that the furnace aperture plug 105 block the aperturesufficiently so as to minimize slag and debris from exiting the furnaceand to minimize ambient air from entering the furnace.

In an exemplary embodiment of the present invention, the furnaceaperture plug 105 is fluid cooled to protect it from the intense heat ofthe furnace. Preferably, the side walls and the front face of the plug105 include fluid channels for cooling the exterior surfaces.Alternatively, the plug may include internal spray nozzles to cool thefront face of the plug from the inside. As shown in FIG. 2, fluid can bechanneled through the plug 105 using fluid inlet 205 and fluid outlet206. Those skilled in the art of steel making are familiar with the useof fluid cooling channels to cool furnace components. The use of fluidcooling channels is particularly desirable on the front face of thefurnace aperture plug 105 because it is exposed to the heat of thefurnace during portions of the melt cycle of the furnace.

In an exemplary embodiment of the present invention, the furnaceaperture plug 105 is retracted by a furnace aperture plug reciprocator110. Alternatively, another device can be used to retract the furnaceaperture plug 105 from the furnace aperture 140. In another alternativeembodiment, the furnace aperture plug 105 can be removed or retractedmanually.

As illustrated in FIG. 2, the furnace aperture plug reciprocator 110 canbe a telescoping arm coupled to the furnace aperture plug 105.Alternatively, the furnace aperture plug reciprocator 110 can be arotating arm that moves the furnace aperture plug using arcuate motion.The furnace aperture plug reciprocator 110 can be coupled to the furnaceaperture plug 105 using any suitable coupling devices including, but notlimited to, a flange 215 extending between the reciprocator 110 and theplug 105. In an alternative embodiment of the present invention, thetelescoping arm may be replaced by an alternative mechanical devicecapable of exerting a force upon the furnace aperture plug 105 toretract and extend the plug 105.

Preferably, the furnace aperture plug reciprocator 110 is controlledautomatically. Additionally, the furnace aperture plug reciprocator 110can be controlled automatically at a predetermined time, or can becontrolled via an operator interface. The operator interface may beimplemented using a switch, lever, software, or other operator interfacemechanism. Alternatively, the furnace aperture plug reciprocator 110 maybe controlled using various devices capable of inserting and retractingthe furnace aperture plug 105.

In accordance with an exemplary embodiment of the present invention, thefurnace aperture plug reciprocator 110 may be adapted to move thefurnace aperture plug 105 through the furnace aperture 140 to clear slagfrom the aperture 140. Additionally, it is typically preferable toextend the furnace aperture plug 105 through the furnace aperture 140periodically during a melt cycle to prevent substantial slag build upfrom clogging the aperture 140, which might otherwise prevent access tothe interior of the furnace 100. Throughout a melt cycle, slag iscreated in the furnace 100 and may build up on any exposed device in thefurnace 100.

If significant amounts of slag build up at the furnace aperture 140, itmay be difficult to remove the slag quickly prior to accessing the meltthrough the furnace aperture 140. The slag can become hard when itadheres to a side wall 160 or to a furnace device, such as the furnaceaccess apparatus 200. If slag builds up over the furnace aperture 140,depending on the level of build up, it may be necessary to clear theslag before accessing the interior of the furnace 100. Accordingly, itis desirable to avoid significant slag build up. An exemplary method forpreventing slag buildup in accordance with the present inventioninvolves reciprocating the furnace aperture plug 105 periodically toclear the aperture 140. The reciprocating motion preferably advances theplug 105 through the aperture 140 a sufficient distance to remove theslag and then returns the plug 105 to its position within the aperture140. Typically, a distance of up to four inches is sufficient to clearthe slag. The forward and back reciprocating motion of the plug 105clears slag from the aperture 140 and prevents large quantities of slagfrom accumulating and hardening around the aperture 140.

In an exemplary embodiment of the present invention, the plug 105 isreciprocated multiple times during a melt cycle, preferably at leasttwice. If reciprocating the plug 105 twice during the melt cycle is notsufficient to keep the furnace aperture clear, the plug 105 may bereciprocated periodically throughout the melt cycle. An exemplary periodfor reciprocating the plug 105 is approximately once every five minutes.In furnace operations where slag buildup is extensive, it may bedesirable to reciprocate the plug 105 at a more rapid rate.

It is desirable for the furnace aperture 140 to be clear of slag whenthe furnace is to be accessed through the furnace aperture 140.Accordingly, it may be desirable to reciprocate the furnace apertureplug just prior to accessing the furnace to remove addition slagproximate the furnace aperture 140.

In an alternative embodiment of the present invention, slag may becleared from the furnace aperture by retracting the furnace apertureplug and injecting a stream of compressed air through the furnaceaperture 140. The stream of air can blow slag away from the aperture140. Alternatively, other gases, or fluids, may be in place of thecompressed air.

As shown in FIG. 3, the furnace mounting enclosure 115 encases thefurnace receptacle 120 and the furnace aperture plug 105. The furnacemounting enclosure 115 is preferably fluid cooled to protect it from theheat in the furnace. As shown in FIG. 3, fluid cooling channel 220 isprovided to direct water, or other cooling fluid, through the furnacemounting enclosure 115.

The furnace mounting enclosure 115 preferably also includes a slopedporch 234 to direct scrap and debris toward the center of the furnace.Additionally, the sloped porch 234 may include corrugations to trap slagon the surface of the enclosure 115 to help insulate the enclosure 115from the heat of the furnace.

FIGS. 4 and 5 are cross-sectioned side views of an exemplary embodimentof a furnace access apparatus mounted in an electric arc furnace, whichis constructed in accordance with an exemplary embodiment of the presentinvention. This embodiment uses a combination furnace aperture burnerand lance 410 instead of a furnace aperture plug 105. Alternatively,either a burner or a lance may be used for the burner/lance 410 in placeof the combination burner and lance. In this description, the term“burner/lance” will be used to refer to a burner, a lance, or acombination burner and lance.

The burner/lance 410 may be operated, at least in part, by aburner/lance reciprocator 440. As illustrated, the burner/lancereciprocator 440 may comprise a telescoping arm 445 coupled to theburner/lance 410. Alternatively, the burner/lance reciprocator 440 canbe a rotating arm that moves the burner/lance 410 using arcuate motion.The burner/lance reciprocator 440 can be coupled to the burner/lance 410using any suitable coupling devices including, but not limited to, aflange 450 extending between the burner/lance reciprocator 440 and theburner/lance 410.

One or more inlets may be provided to introduce elements into theburner/lance 410. For example, and not limitation, a fuel inlet 420 actsas a means for introducing fuel for the burner/lance 410 to burn.Additionally, an oxygen inlet 425 may be provided to allow oxygen to beintroduced to the melt 150. When performing as a lance, the burner/lance410 may blow oxygen into the melt 150 during refinement to assist indecarburizing the melt 150 by oxidizing carbon contained in the bath.The rate at which oxygen is injected into the melt 150 may determine arate of decarburization, such that increasing the rate of oxygeninjection may result in an increased decarburization rate.

The burner/lance 410 is connected to the furnace 100, aligned with thefurnace aperture 140. The burner/lance 410 may replace the furnaceaperture plug 105 or may be used in addition to the furnace apertureplug 105. While the furnace aperture plug 105 would reduce slag byblocking the furnace aperture 140, the burner/lance 410 may prevent orminimize slag build-up by maintaining a flame 430 (FIG. 5) at thefurnace aperture 140 and directing such flame 430 into the furnace 100.

When the burner/lance 410 is engaged, it maintains a flame at thefurnace aperture 140. To access the melt 150, the burner/lance 410 isdisengaged to allow access through the furnace aperture 140. Disengagingthe burner/lance 410 may include the burner/lance reciprocator 440retracting the burner/lance 410 from the furnace aperture 140. When theburner/lance 410 is disengaged, its flame may be extinguished, andinjection of fuel and oxygen through the inlets 420 and 425 maytemporarily cease. FIG. 4 illustrates the burner/lance 410 in aretracted position. After retraction of the burner/lance 410, the melt150 may be accessed. For example, and not limitation, a furnace probe125 (FIG. 7) may be inserted through the furnace aperture 140 when theburner/lance 146 is retracted.

When access to the furnace aperture 140 is no longer needed, theburner/lance 410 is returned to its position in the furnace aperture 140and is reengaged. The burner/lance 410 is reignited when reengaged. FIG.5 illustrates the engaged burner/lance 410 inserted into the furnaceaperture 140. Preferably, the burner/lance 410 is engaged except whenaccess to the furnace via the furnace aperture 140 is needed. When theburner/lance 410 provides such a constant flame, the resulting heat atthe furnace aperture 140 prevents the build-up of slag. As a result of,the furnace aperture 140 can be accessed without the need to remove asmuch slag as would otherwise build up.

Each operation of the burner/lance 410, including combustion andretraction, may be implemented manually or, alternatively, may beprogrammed for automatic operation. For example, and not limitation, theburner/lance 410 may have a switch or lever for extinguishing the flame430, and a handle for manually retracting the burner/lance 410 from thefurnace aperture 140. Additionally or alternatively, the burner/lance410 may be programmed to maintain the flame 430 for a certain duration,to extinguish the flame 430, and then to retract according apredetermined schedule. Many combinations of automatic and manualoperations of the burner/lance 410 may be implemented. For furtherexample, the burner/lance 410 may have an automated process ofretracting the burner/lance 410 as well as a manual process ofextinguishing the flame 430. It is desirable that, if the burner/lance410 implements an automatic operation, the burner/lance 410 also allowsmanual override of such automatic operation.

Like the furnace aperture plug 105 operation, the burner/lance 410 maybe extended through the furnace aperture 140 to push out any remainingslag. Such operation is desirable because it can be dangerous to ignitethe burner/lance 410 if slag blocks the furnace aperture 140. Ifdesired, the burner/lance reciprocator 440 may repeatedly reciprocatethe burner/lance 410 to break up slag that has formed proximate thefurnace aperture 140.

Those of skill in the art will appreciate that the burner/lance 410 canbe replaced by a burner or a lance, and the combination is not required.Those skilled in the art will further recognize that, where use of afurnace aperture plug 105 is indicated, a burner/lance 410 could be usedalternatively or additionally. Further, the burner/lance 410 may be usedin place of the furnace aperture plug 105 and in accordance with otherembodiments described herein.

FIG. 6 is a cross-sectioned side view of the furnace access apparatusshowing the aperture plug in both a retracted position and an insertedposition. The solid lines in FIG. 6 show the furnace aperture plug 105in a retracted position and the dashed lines illustrate the movement ofthe plug 105 to a closed position and also the reciprocating movement ofthe plug 105. FIG. 6 illustrates the relationship between the furnaceaperture plug 105 positions in FIGS. 2 and 3.

The discussion below pertains to the use of the furnace access apparatusin three exemplary embodiments of the present invention, including theuse of the furnace access apparatus to probe the characteristics of themelt, the use of the furnace access apparatus to insert chemicals intothe melt, the use of the furnace access apparatus for granting accessfor a burner device, and the use of the furnace access apparatus forinsertion of a lance device. Those of skill in the art will appreciatethat these are simply four exemplary embodiments of the furnace accessapparatus and numerous other embodiments of the furnace access apparatusare possible.

Probing

A notable part of the steel making process is the determination of thecharacteristics of the melt 150. Moreover, prior to removing portions ofthe melt 150 from the furnace 100, it is important to verify that themelt 150 has reached the appropriate temperature and has the desiredcharacteristics. In an exemplary embodiment of the present invention,the temperature and chemical characteristics of the melt 150 can bemeasured using a probe. Those of ordinary skill in the art will befamiliar with various probes available for measuring temperature andchemical composition of the melt 150.

As shown in FIG. 7, in an exemplary embodiment of the present invention,the furnace receptacle 120 is capable of receiving a furnace probe 125when the furnace aperture plug 105 has been removed from the furnaceaperture 140 by the furnace aperture plug reciprocator 110. Thereby, thefurnace probe 125 is permitted to pass through the furnace aperture 140and into the melt 150 (FIG. 1).

The furnace receptacle 120 is typically slanted downward at an angle,preferably between 30-60 degrees, to allow access through the furnaceaperture 140 toward the metal melt 150 (FIG. 1) in the hearth of thefurnace 100 (FIG. 1). To promote measurements being taken easily fromthe side wall 160 (FIG. 1), it is preferable that the probe 125 isinserted at an angle which is neither too shallow nor too steep. If theangle is too steep, the probe may contact the hearth of the furnace 100on the low end, yielding inaccurate measurements, or interfere with thesidewall fluid cooled elements in the upper shell on the high end. Ifthe angle is too shallow, an exceptionally long probe may be required toreach into the melt 150 (FIG. 1). More preferably, an angle ofapproximately 45 degrees (+/−15 degrees) is used.

In an exemplary embodiment of the present invention, the furnacereceptacle 120 is preferably cylindrical in shape with an enlarged,funnel shaped, opening for directing the furnace probe 125 through thefurnace aperture 140. Additionally, as shown in FIG. 7, the furnacereceptacle 120 may include a compressed air channel 210 for injectingcompressed air through the furnace receptacle 120 and the furnaceaperture 140. The compressed air can blow any slag or debris away fromthe furnace aperture 140 when the furnace aperture plug 105 isretracted. It is preferable to inject compressed air through the furnaceaperture 140 whenever the furnace aperture plug 105 is in a retractedposition.

In an alternative embodiment of the present invention, the furnaceaperture plug 105 may be omitted and a stream of compressed air can becontinuously injected through the aperture to keep the opening free ofslag and debris. Typically, this is not a desirable solution, due to thecost of continuously injecting compressed air and its cooling affect onthe molten metal.

In an exemplary embodiment of the present invention, the furnacereceptacle 120 includes a trigger for automatically injecting compressedair through the furnace aperture 140 when the furnace aperture plug 105is retracted. Additionally, the trigger may be adapted to automaticallyshut off the compressed air flow when the furnace aperture plug 105 isreinserted into the furnace aperture 140.

In FIG. 7, the furnace access apparatus 200 is shown with the furnaceaperture plug 105 retracted away from the furnace aperture 140. In use,the furnace aperture plug 105 is retracted to clear the furnace aperture140 for insertion of a furnace probe 125. As is shown in FIG. 7, thefurnace receptacle 120 directs a furnace probe 125 through the furnaceaperture 140. Thus, the furnace probe 125, via the furnace receptacle120, and the furnace receptacle plug 105 may be inserted into the sameaperture. In addition to the probe 125, a temperature measuring deviceor many different types of lances may be inserted through the furnaceaperture 140.

FIG. 7 also illustrates that the furnace probe 125 and the furnacereceptacle 120 have intersecting paths. In order for the probe 125 to beinserted through the furnace aperture 140, the furnace aperture plug 105should be retracted sufficiently to allow passage of the furnace probe125. FIG. 7 illustrates this relationship as the furnace aperture plug105 is retracted clear of the path of the probe 125.

Chemical Insertion

As previously described, the furnace access apparatus 200 providesaccess to the melt in a position sufficiently proximate the melt toallow for efficient and effective access to melt for a variety of tasks.In addition to probing the melt, another task that is typicallydesirable for creating and maintaining an efficient steel making processis the insertion of certain chemicals or other materials into the melt.For example, chemicals such as, but not limited to, lime, calcium,carbon, oxygen, aluminum, silicon, slag conditioners, and ferro-alloyadditives, may be introduced into the bath to alter the chemicalcomposition of the steel, alter the steel making process, or protect thefurnace equipment.

In a non-limiting example, the chemical composition of the molten meltcan be altered to reduce the carbon content to a selected level inaccordance with the desired quality of the steel to be created.Decarburization, the process of reducing carbon content, can involvevarious steps in which substances are introduced into the melt that leadto a decrease in the percentage of carbon present in the melt. In anon-limiting example, the insertion of lime, along with other chemicals,decarburizes the melt. The insertion of lime aids in the formation of aninsulating foamy slag layer in the furnace, which decreases heat lossfrom the melt surface, reduces energy costs, and protects the furnacecomponents.

FIG. 8 is a cross-sectioned side view of an alternative embodiment ofthe furnace access apparatus mounted in an EAF. As shown in FIG. 8, thefurnace access apparatus 200, in accordance with an exemplary embodimentof the present invention, generally includes, but is not limited to, afurnace aperture 140, a furnace aperture plug reciprocator 110, and afurnace receptacle 120. In an exemplary embodiment, the furnacereceptacle 120 is aligned with the furnace aperture 140 for accessingthe interior of the furnace when the furnace plug is retracted. In anexemplary embodiment depicted in FIG. 8, the furnace access apparatus200 includes a chemical receptacle 605. In an exemplary embodiment, thechemical receptacle 605 is connected to the furnace receptacle 120 by aconnecting device 610.

When the furnace aperture plug 105 is in the retracted position, asshown in FIG. 8, the furnace aperture 140 provides access to the melt150 in a position sufficiently proximate the melt 150 to allow forefficient and effective access to melt 150 for chemical insertion. In anexemplary embodiment, this chemical insertion is accomplished byinserting a chemical into the chemical receptacle 605, which passes thechemical through the furnace receptacle 120, through furnace aperture140, and into the melt 150.

In providing for chemical insertion into the furnace, it is oftenpreferable to insert chemicals into the furnace at a desired locationand a desired angle. Just as the location of the furnace aperture 140may provide a preferred position and angle for access to the melt 150for probing purposes, the furnace aperture 140 may provide a preferredposition and angle for access to the melt 150 for the insertion ofchemicals. More particularly, the close proximity of the furnaceaperture 140 to the melt 150, due to its placement near the sill line155, provides for efficient and effective insertion of chemicals intothe melt 150. In exemplary embodiment, the furnace access apparatus 200,is preferably mounted adjacent an opening in the fluid cooling side wallpanel 160 of the furnace 100. In the illustrated embodiment, themounting enclosure 115 preferably rests on the step 130 formed betweenthe panels of the side wall 160 of the upper shell of the furnace 100and the refractory wall of the hearth 135. Alternatively, the furnaceaccess apparatus 200 could be supported or suspended from anothersuitable structural member of the furnace 100.

FIG. 9 is a cross-sectioned side view of the furnace access apparatusillustrated in FIG. 8. In an exemplary embodiment of the presentinvention, as shown in FIG. 9, the furnace receptacle 120 is capable ofreceiving chemicals, which can then pass through the furnace aperture140 and into the melt. As previously mentioned, the furnace receptacle120 may include a compressed air channel 210. Through this compressedair channel 210, air can be introduced into the furnace through thefurnace aperture 140 when the furnace aperture plug 105 is retracted. Inthe exemplary embodiment depicted in FIG. 9, the furnace receptacle 120is enabled to provide for the insertion of chemicals into the melt, inaddition to that of air through the compressed air channel 210.

In the exemplary embodiment depicted in FIG. 9, a chemical receptacle605 is provided that can be connected to the furnace receptacle 120. Inone embodiment, the chemical receptacle 605 is tubing through whichchemicals are passed. In alternative embodiments, the chemicalreceptacle 605 may be piping or simply a funnel with an opening capableof being accessed by an operator.

In an exemplary embodiment, the furnace access apparatus 200 enables thefurnace operator to manually or automatically insert a predeterminedamount of a chemical substance into the melt 150 (FIG. 1). In anon-limiting example, the operator may insert a specific amount of limethrough the chemical receptacle 605, through the furnace aperture 140,and into the melt 150 (FIG. 1).

In some embodiments, the operator may automatically insert a specifiedamount of a chemical substance at a specific point in the process. Thisautomatic insertion of a chemical substance may be associated with aspecific time in the steel making process, or be associated with certaintrigger parameters, such as when the melt reaches a certain chemicalcomposition or when the temperature rises to a certain level. In otherembodiments, the operator, may manually insert the chemical substances.

Additional Lance Devices

In an alternative embodiment of the furnace access apparatus 200, thefurnace aperture 140 is capable of receiving a lance device. Lances areused to insert or inject a chemical substance into the melt to changethe chemical characteristics of the melt.

Those of skill in the art will appreciate that a wide variety of lancedevices are available and any of these devices could be used withoutdetracting from the scope of the invention. In a non-limiting example, alance device could be an oxygen lance, a carbon injection device, or adevice providing a combination thereof.

It is typically desirable in efficient and effective steel making to beable to lance oxygen or other substance throughout a number of reactionzones within the iron carbon melt. In an exemplary embodiment, thefurnace access apparatus 200 provides the operator with a preferableposition within the furnace to insert chemicals through a lance.

The furnace access apparatus 200 may include a lance device capable ofbeing inserted through the furnace aperture 140 when the furnaceaperture plug 105 has been removed by the furnace aperture plugreciprocator 110. In a non-limiting example, the operator could removethe slag buildup around the furnace aperture 140 through the use of thefurnace aperture plug reciprocator 110, then remove the furnace apertureplug 105 and insert the lance device into the furnace through thefurnace aperture 140.

The furnace access apparatus 200 permits the operator to insert thelance device through the furnace aperture 140 and into the interior ofthe furnace. The lance device can be inserted by a variety of differentmechanisms and configurations. In an exemplary embodiment, the lancedevice is attached to a reciprocating device that is similar to thefurnace aperture plug reciprocator 110 for the furnace aperture plug105. Thereby, when the furnace aperture plug 105 is removed from thefurnace aperture 140, the lance device is then inserted through thefurnace aperture 140 by another reciprocating device attached to thelance device. In an alternative embodiment, the lance device is operatedmanually and when the furnace aperture 140 is open, the lance device canbe inserted through the furnace aperture 140. Those of skill in the artwill appreciate that the lance could be inserted through furnaceaperture 140 by a variety of methods and devices without detracting fromthe scope of the invention.

Upon completion of the use of the lance device, the lance device may beremoved from the furnace aperture 140. Once the lance device has beenremoved from the furnace aperture 140, the furnace aperture plugreciprocator 110 may reinsert the furnace aperture plug 105 into thefurnace aperture 140. As previously provided, the furnace aperture 140may be kept free of slag through the reciprocation of the furnaceaperture plug 105 by the furnace aperture plug reciprocator 110; thuspermitting unobstructed access to the melt by the lance device uponinsertion into the furnace aperture 140.

The lance device may be configured to penetrate beyond the furnaceaperture 140 and into the interior of the furnace 100. In a non-limitingexample, the reciprocator attached to the lance device may cause thelance device to protrude a distance beyond the furnace aperture 140 andinto the furnace 100.

While the various embodiments of this invention have been described indetail with particular reference to exemplary embodiments, those skilledin the art will understand that variations and modifications can beeffected within the scope of the invention as defined in the appendedclaims. Accordingly, the scope of the various embodiments of the presentinvention should not be limited to the above discussed embodiments, andshould only be defined by the following claims and all applicableequivalents.

1. A furnace access apparatus for enabling access to a metal meltfurnace, the furnace access apparatus comprising: a mounting enclosurecomprising a furnace aperture, a first passage and a second passage, andadapted for mounting in said furnace; a furnace aperture burner/lanceadapted for insertion into the furnace aperture through the firstpassage and adapted to direct a burner/lance output toward a furnacemelt; and a mechanized furnace aperture burner/lance reciprocator thatis remotely controlled, the furnace aperture burner/lance reciprocatorcoupled to the furnace aperture burner/lance and adapted to retract thefurnace aperture burner/lance from the furnace aperture into the firstpassage while the furnace is in use; wherein the furnace aperture isadapted to allow access to the furnace through the second passage whilethe furnace aperture burner/lance is retracted from the furnace apertureand is at least partially within the first passage.
 2. The apparatus ofclaim 1, the furnace aperture burner/lance comprising a burner fordirecting a flame into the furnace through the first passage and thefurnace aperture.
 3. The apparatus of claim 2, further comprising a fuelinlet for introducing fuel to the burner.
 4. The apparatus of claim 1,the furnace aperture burner/lance comprising a lance device.
 5. Theapparatus of claim 4, the lance device adapted to inject oxygen into thefurnace.
 6. The apparatus of claim 5, further comprising an oxygen inletadapted to introduce oxygen to the lance device for injection into thefurnace.
 7. The apparatus of claim 1, the furnace aperture burner/lancecomprising a combination burner/lance for directing a flame andinjecting oxygen into the furnace through the first passage and thefurnace aperture.
 8. The apparatus of claim 1, further comprising afurnace access receptacle aligned with the second passage and thefurnace aperture for accessing the interior of the furnace when thefurnace aperture burner/lance is retracted.
 9. The apparatus of claim 8,wherein the furnace access receptacle is adapted to receive a furnaceprobe when the furnace aperture burner/lance is retracted.
 10. Theapparatus of claim 8, wherein the furnace access receptacle is adaptedto receive chemicals for injection into the furnace melt.
 11. Theapparatus of claim 1, wherein the furnace aperture burner/lancereciprocator comprises a telescoping arm.
 12. The apparatus of claim 1,wherein the furnace aperture is adapted to receive a second lance devicethrough the second passage when the furnace aperture burner/lance isretracted.
 13. The apparatus of claim 1, wherein the furnace apertureburner/lance is further adapted to extinguish the flame when the furnaceaperture burner/lance reciprocator retracts the furnace apertureburner/lance.
 14. The apparatus of claim 1, wherein the furnace apertureburner/lance reciprocator is adapted to move the furnace apertureburner/lance linearly.
 15. The apparatus of claim 1, wherein the furnaceaperture burner/lance reciprocator is adapted to move the furnaceaperture burner/lance in an arcuate motion.
 16. The apparatus of claim1, wherein the furnace aperture burner/lance reciprocator is adapted tomove the furnace aperture burner/lance by automatic operation.
 17. Afurnace melt chemical insertion apparatus for enabling chemicalinsertion into a metal melt furnace, the furnace melt chemical insertionapparatus comprising: a furnace aperture burner/lance adapted forinsertion into a furnace aperture of a furnace access apparatus, whereinthe furnace access apparatus comprises a first passage and a secondpassage; and a mechanized furnace aperture burner/lance reciprocatorthat is remotely controlled, the furnace aperture burner/lancereciprocator adapted to retract the furnace aperture burner/lance fromthe furnace aperture into the first passage while the furnace is in use;and a chemical receptacle for receiving and directing a chemical throughthe second passage and the furnace aperture when the furnace apertureburner/lance is retracted and is at least partially within the firstpassage.
 18. The apparatus of claim 17, the furnace apertureburner/lance comprising a burner for directing a flame into the furnacethrough the first passage and the furnace aperture.
 19. The method ofclaim 17, the furnace aperture burner/lance comprising a lance devicefor injecting oxygen into the furnace.
 20. The apparatus of claim 17,the furnace aperture burner/lance comprising a burner for directing aflame and a lance device for injecting oxygen into the furnace throughthe first passage and the furnace aperture.
 21. The apparatus of claim17, wherein the chemical directed through the furnace aperture is one oflime, carbon, calcium, particulate material, and slag conditioner.